Serial Attached SCSI (SAS) is the next generation of the Small Computer System Interface (SCSI), used for connecting storage devices to a computer system. It has been developed as an alternative to the Fibre Channel interface (FC), offering similar performance and reduced cost, at the expense of connectivity and scalability.
Tunneling through a Fibre Channel link with SAS traffic introduces the problem of discovery of the SAS devices when a new tunneling extender is introduced into a Fibre Channel fabric. The SAS devices attached to the new tunneling extender will not be visible to the other SAS devices attached to other remote SAS extenders without a new process for initiating discovery.